1. Field of the Invention
The present invention concerns security electrical power distribution systems for light aircraft equipped for flight on instruments.
2. Description of the Prior Art
Currently, the electrical power supply for the instrument panel of a light aircraft is of the same type as in a terrestial automotive vehicle, comprising a 12 or 24 Volt battery and a generator (alternator) driven by the motor. This combination is generally connected to a distribution bus to which the various navigation and radio equipments are connected. This arrangement is used in aircraft equipped for flight on instruments (in zero visibility).
While navigation and radio instruments are duplicated for reasons of security, this is not the case with the electrical power distribution system, which is normally provided by a single bus. The potential hazards of this situation are readily apparent. In the event of a fault such as a short-circuit at or failure of the generator, the aircraft may find itself without power for its flight instruments, in the longer or shorter term. Although the aircraft can continue to fly without an electrical power supply to its instrument panel, such a failure presents two types of hazard. The first is that of loss of use of navigation systems. The second is due to the fact that light aircraft equipped for flight on instruments are increasingly using the air lanes used by large commercial aircraft, with the attendant risk of a mid-air collision.
Should a fault occur in the generator, battery or main distribution bus, the pilot needs to know as soon as possible and to continue to have power available for sufficient time to shorten or terminate the flight.